Positive action clamshell boom mounting



Oct. 9, 1956 A. o. HELLERUD 2,765,939

POSITIVE ACTION CLANSHELL BOOM MOUNTING Filed May l5, 1952 2 Sheets-Sheet 1 ATTORNEYS Get. 9, 1956 A. o. HELLERUD 765,939

POSITIVE ACTION OLANSNELL BOOM MOUNTING Filed May l5, 1952 2 Sheets-Sheet 2 ATTORNEYS POSITIVE ACTION CLAMSHELL BOOM MOUNTING Arthur 0. Helierud, Pierce, Idaho Application May 13, 1952, .Serial No. 287,569 2 Claims. (Cl. 214-147) machine, and rotated by a motor on the end of a boom stick, and wherein slack in the 'cables is taken up by an auxiliary drum actuated Vby magnetic action through a dragging clutch whereby tension is maintained in the cables continuously.

The purpose of this invention is to provide means for mounting a clamshell or tongs on the ,end of a lboom stick whereby the gripping elements may be accurately positioned to facilitate picking up objects and also -for depositing objects in predetermined positions.

in the conventional type .of clamshell mounting the gripping elements are suspended by cables so that it is necessary to swing the end of the lboom stick from one position to .another Vin order to drop the gripping element over an object and with aiiexible mounting of this type it is diflicult to position the gripping elements from the cab of the machine. With this thought in mind this invention contemplates an improved mounting `wherein the gripping elements are directly connected to vthe end of a boom stick so that the elements follow the boom stick, and with the elements rotatably mounted `in a vertically disposed position and controlled by a motor the elements may readily be 'turned to such a position that they may be dropped over an object or on opposite sides ot a pole or the like.

Furthermore in the conventional 'type 'of mounting the gripping elements are dropped 'by releasing a cable and when the gripping elements engage an object or drop upon the surface the cable is released and it is difficult to take up the slack therein without closing the gripping elements. For this reason the improved mounting of this invention includes an auxiliary drum with tensioning means therein whereby tension is maintained in the cable continuously.

The object of this invention is, therefore, to provide means for directly mounting a clamshell or tongs on the end of a boom stick whereby digging or gripping elements are under the control Aof .an operator .continuously.

Another object of the invention yis to provide means tor mounting gripping .elements on `the end of .a boom stick lwhereby the gripping .elements may be positively turned to facilita-te picking up different types :of objects.

A further object of the invention is to provide :an iinproved mounting for gripping velements on the end V'of a boom or boom stick in which the mounting is, kof a comparatively simple and economical construction.

With these and other objects and advantages in view the invention embodies a machine of the steam shovel type having a boom pivotally mounted on the end of a platform with a boom stick pivotally and slidably mounted on the boom and with gripping elements journaled in the extended end of the boom stick and elevated,

...tes Patent O The boom stick 12 is drawn 2,765,939 vPatented Oct. 9, 1956 "2 rotated, and opened and closed from va cab on the plat- `form on which the boom is pivotally mounted.

Other features and advantages of the invention will appear from the following description taken in connection with the drawings, wherein:

Figure 1 is la side elevational View showing one end of a machine, such as an excavator and illustrating ,a mounting wherein gripping tongs Vare journaled on the of a boom stick carried by a `boom extended from la platform of the machine.

Figure 2 Ais a plan view showing the outerend of the boom stick with the parts shown on an enlarged scale and illustrating the elements for rotating the gripping tongs.

Figure 3 is a detail showing a vvertical section through the rotary mounting of a gripping element on the extended end of a boom stick.

Figure 4 is a side elevational View also showing a rotary mounting of the bearing on .the end 0f the boom stick, illustrating a modication ywherein the mounting is pivotally mounted, and showing the position of the boom stick with a cable extended through the 'bearing in full lines in one position and in Vdotted lines in another position.

Figure 5 is an end ing on the endof a Figure 4.

Figure 6 is a vertical section .through the bearing shown in Figure 5.

4Referring now to the drawings wherein like refer- .ence characters denote corresponding parts the improved clam or tong mounting of this invention includes a cylinder 10 mounted in the end of a boom or dipper stick 12 with tongs 13 and 14 pivotally `mounted on tongues 1S and '16, respectively, extended from a bearing sleeve 17 rotatably mounted in the cylinder 10 and the bearing is rotated by a motor 18 through a reduction gear '1'9 with a chain 20 that is trained over a sprocket 21 on the .reduction gear and also over a sprocket 22 on a iiange 23 'that is secured to the upper end of the bearing 17 with bolts 24.

The boom or dipper stick 1'2 elevational view showing the bearboom stick, of the type shown in is slidably mounted `in a hanger `25 that .is pivotally mounted by a pin 26 on a boom 27 and Vthe boom is pivotally mounted on a platform '28 of a machine 29 with la pin 30.

The boom stick 12 is moved outwardly by a cable 31 which is trained over a pulley 32 on the boom and a pulley 33 lon the boom stick and the end of the cable ythe point 34. The cable '31 extends 'to a suitable drum in the cab of the machine. inwardly with a cable 35 that extends over a pulley or sheave similar to the pulley 33 Land the end thereof is Aattached to the cab, as indicated by the numeral 136, at the point 37. The cable 35 also extends to a drum in the cab.

The elevation of the extended end of the boom stick 12 is controlled Sby a cable 38 that extends from a drum Vin the cab 36 over one of the sheaves 39 and also over one of the sheaves 40, from which the cable extends through .a pulley block 4.1 and back to an eye on the `boom 27.

The gripping vtongs 13 and14 are controlled with a similar cable 43 that yextends over vthe sheaves 39 and 4t) and around a pulley block 44 to the eye 42. The pulley block 44 is secured to the upper end of a cable 45 that extends over apulley 46 in a bracket 47 and through an opening 48 in the bearing 17 'to a latch 49, pivotally mounted by a bolt 50 on toggle levers 51 and S2 which are pivotally connected to the tongs 13 and 14, respectively, with pins 53 and 54. The cable 45 is trained over a pulley 55 that is journaled by a pin 56 in an arm 57 of the tong 13.

The extended end of the boom 27 is controlled with a cable 58 one end of which is secured to the bracket 59 in which the sheaves 39 are journaled, at the point 60, and the opposite end of which extends into the cab 36 wherein it is trained over a drum for operating the boom. From the point 60 the cable 38 1extends around one of the sheaves 40 which are journaled on a pin 61 in the end of the boom and also over one of the sheaves 39 which are journaled on a pin 62 in the bracket 59.

With the parts arranged in this manner the cable 58 provides the boom line, the cable 43 the hoisting line and the cable 38, the auxiliary holding line which, being controlled by tension action in the drum, or with a magnetic or dragging clutch, is retained in constant tension so that the operator has absolute control over the parts continuously.

The boom or dipper stick 12 is provided with stops 63 and 64 to limit travel thereof and power may be supplied to the motor 18 through a hose or an electric cable, as indicated by the numeral 65.

The gripping elements or tongs 13 and 14 are pivotally mounted with arms 57 and 66 on the tongues 1S and 16 with pins 67 and 68, and wherein the gripping elements are illustrated as being in the form of tongs, it will be understood that a clamshell bucket or other digging or gripping elements may be attached to the mounting at the end of the boom stock.

The boom stick 12 is extended or retracted by the cables 31 and 35, respectively and, as illustrated in Figure 1, the cables extend over sheaves 33 journaled by a pin 67 in a bracket 68 on the end of the boom stick, and the cable 31 also extends over the pulley 32 that is journaled by a pin 70 in a bracket 71 on the boom 27.

In the design illustrated in Figures 1, 2, 3, the bearing housing is rigidly mounted on the end of the boom stick and the motor 18 and speed reduction unit 19 are mounted on the side thereof.

In the design illustrated in drical housing 80, similar to mounted with trunnions 81 and 82 in arms 83 and 84, respectively, which are secured on the sides of a boom stick 85, similar to the boom stick 12, with bolts 86. The trunnions are provided with cotter pins 87 and washers 88.

The arms 83 and 84 are also provided with links 39 and 90, having elongated slots 91 therein, and the links, which are pivotally connected to the arms 83 and 84 with pins 92, are secured to the sides of the housing 80 with studs 93. By this means the bearing housing is pivotally mounted in the extended end of the boom stick and the housing is retained in adjusted positions with nuts 94 on the studs 93.

In this design a bearing sleeve 95 is journaled in the housing 80 and the lower end of the sleeve is provided with an annular collar 96 that is positioned to engage the lower end of the housing. The lower end of the sleeve is provided with ears 97 and 98 to which arms 99 and 100, similar to the arms 57 and 66, are pivotally connected and the lower end of the sleeve is also provided with rollers 101 and 102 through which a cable, similar to the cable 45 passes.

A sprocket 103, similar to the sprocket 22, is mounted on the upper end of the bearing sleeve 95 and the sleeve is rotated by a chain 104 with the chain trained over the sprocket 103 and also over a sprocket 105 on a shaft 106 of a motor 107. The motor 107 is mounted directly on the outer surface of the housing 80, as shown in Figures 4 and 5. By this means a clam or tongs depending from the lower end of the bearing sleeve 95 may readily be turned from one position to another from the cab of the machine.

The boom stick 85 is also provided with Figures 4, 5, and 6 a cylinthe housing 10 is pivotally outwardly exaffermata A f 4 tended arms 108 and 109, in extended ends of which `a pulley 110 is journaled on` a pin 111, and a cable 112, which is similar to the cable 45, is trained over this pulley and this cable also extends between the pulleys 101 and 102 in the lower end of the bearing sleeve.

A clamshell bucket, tongs, or other gripping elements may therefore, be journaled in a bearing housing rigidly mounted on the extended end of a boom or a clipper stick, as shown in Figure l, or the housing may be pivotally mounted, as illustrated in Figures 4, 5, and 6, and with the parts arranged in this manner an operator in the cab ofthe machine may rotate the gripping elements to facilitate picking up objects, such as a telephone pole, conduit, or the like, and by the same means the objects may be positioned so that they may be dropped into comparatively crowded areas, before they are released by the gripping elements.

It will be understood that modifications within the scope of the appended claims may be made in the design and arrangement of the parts Without departing from the spirit of the invention.

What is claimed is:

l. In a gripping element mounting for excavating and hoisting machines, the combination which comprises, a boom, a boom stick pivotally and slidably mounted on said boom, a cylindrical vertically disposed bearing housing carried by the extended end of said boom stick, a bearing sleeve journaled in said bearing housing, gripping elements pivotally mounted on the lower end of the bearing sleeve, a motor carried by said boom stick, means operatively connecting the motor to the bearing sleeve for rotating the sleeve, a pulley block positioned above the bearing, a cable extended from the pulley block through the sleeve to the gripping elements for lactuating said gripping elements, a hoisting cable trained over a pulley in the pulley block and extended therefrom, and an auxiliary holding cable extended from the extended end of said boom stick.

2. In a gripping element mounting for excavating and hoisting machines, the combination which comprises, a boom, a boom stick pivotally and slidably mounted on said boom, a cylindrical vertically disposed bearing housing carried by the extended end of said boom stick, a bearing sleeve jonrnaled in said bearing housing, gripping elements p'votally mounted on the lower end of the bearing sleeve, a motor carried by said boom stick, means operatively connecting the motor to the bearing sleeve for rotating ithe sleeve, a pulley block positioned above the bearing housing, a cable extended from the pulley block through the sleeve to the gripping elements for actuating said gripping elements, a hoisting cable trained over a pulley in the pulley block and extended therefrom, an auxiliary holding cable extended from the extended end of said boom stick and means adjusting the position of the bearing housing in relation to the boom stick` References Cited in the file of this patent UNITED STATES PATENTS 994,506 Falcone Iune 6, 1911 1,236,418 Fogarty Aug. 14, 1917 1,327,324 Hecker Jan. 6, 1920 1,518,560 Carroll Dec. 9, 1924 1,604,639 Fogarty Oct. 26, 1926 2,196,649 Waite Apr. 9, 1940 2,486,479 Kennedy NOV. l, 1949 2,577,689 Morin Dec. 4, 1951 2,613,831 Rees Oct. 14, 1952 2,656,059 Troyer Oct. 20, 1953 2,685,974 Kern Aug. 10, 1954 

